Any theory of the quark confinement should be able to explain these features of the confining force. The domain structure model has been fairly successful in describing the mechanism of confinement in QCD [1]}, [2]}. The model assumes that the vacuum is filled with domains. In \(SU(N)\) , there are \(N\)  types of domains including \(N-1\)  types of center vortices corresponding to
the non-trivial center elements of \(z_n=\exp (i2\pi n/N)\)  where the value \(n=1,...,N-1\)  and vacuum type corresponding to the trivial center element \(z_0=1\)  (\(n=0\) ).
The effect of a domain on a planar Wilson loop is to multiply the loop by a group factor
\({G}_r(\alpha ^{n}_C(x))={1}/{d_r}\text{Tr}~\exp [i\vec{\alpha }^{n}_C\vec{{H}}],\) 
